1. Field of the Invention
The present invention relates to motor vehicles, and especially their steering columns, and its subject is more particularly a motorized device for controlling and adjusting the position of an adjustable steering column.
2. Description of the Prior Art
The current trend in the automotive industry is not only toward improving the technical performance of vehicles, but also toward improving the comfort of the occupants and especially that of the driver so as to be able to adapt, at least partially and locally, the geometry of the passenger compartment to the shape of a passenger, and in particular of the driver. This is particularly so for the steering wheel which terminates the steering column. The position of the steering wheel, in terms of depth and inclination, can be selected and fixed as a function of the state of the seats of the vehicle and as a function of the shape of the driver and of his style of driving.
Motor vehicles which are equipped with steering columns which can be adjusted in terms of depth and/or inclination are in some cases currently motorized, making use of separate electric motors for the control and the adjustment of the depth and for the control and the adjustment of the inclination. These special motors for the two degrees of freedom, which are usually movable, are also associated with special transmissions for each degree of freedom.
It can easily be seen that the use of two motors and two transmissions increases costs both because of the supplying of the components and because of their assembly and their fitting. In addition to this economical aspect, there should also be mentioned the constraints which result from the maintenance and the overhauling or repair involved with the existence of relatively numerous and complex components, the presence of which only increases the risks of failure.